Apparatus and method for closing a septal defect

Abstract

A catheter delivered device to close a septal defect, the device comprising a cylindrical shaft of metal or polymeric material with concentric parallel cuts through the wall of the device which create flattened support struts. The center of the support struts move radially away from the axis in a hinge like fashion in response to the movement of the device's proximal and distal ends toward the center of the device. This movement is reversibly effected through mechanical means. The device can be coated with growth factors, mitogenic factors or other determinants which can improve tissue growth such that tissue ingrowth can occur over a period of time. The catheter itself may be an ultrasonic imaging catheter.

What is claimed is: 
     
       1. An apparatus for reversibly closing a septal defect, the apparatus comprising: a) a septal defect closure device that is unitary in construction and comprises a first end, a second end and a center portion, said septal defect closure device having a first configuration comprising a scored, cylindrical shaft having an axis therethrough;   b) a catheter delivery means; and   c) an intralumen mechanical mechanism located in the catheter delivery means; whereby when the device is delivered to an area having a septal defect such that the center portion of the shaft is positioned in the defect, at least two support struts are created as the intralumen mechanical mechanism begins to pull the first and second ends of the shaft toward the center portion thereof, the struts moving radially away from the axis in a hinge like fashion, thereby causing the septal defect closure device to assume a specific second configuration which fits securely into the septal defect and spans both sides of the septal defect, said septal defect closure device in its second configuration being anchored to the septal defect by pressure, causing the defect to be reversibly closed.   
     
     
       2. The apparatus of claim 1 wherein the septal defect closure device further comprises locking means for reversibly locking the device. 
     
     
       3. The apparatus of claim 1 wherein the septal defect closure device further comprises a plurality of tissue hooks located thereon to anchor the device in place in the septal defect. 
     
     
       4. The apparatus of claim 1 wherein the septal defect closure device is made of a biocompatible material. 
     
     
       5. The apparatus of claim 4 wherein the biocompatible material is a nonbiodegradable, biocompatible polymeric material. 
     
     
       6. The apparatus of claim 1 wherein the septal defect closure device is made of a polymeric material selected from the group consisting of thermosetting polymers, thermoplastic polymers, thermoplastic elastomers, elastomers, composites, pseudo-thermoplastics, carbohydrates, proteins, and mixtures thereof. 
     
     
       7. The apparatus of claim 1 wherein the septal defect closure device is made of a polymeric material selected from the group consisting of polycarbonate urethanes, polyether urethanes, polyethyleneterephthalate, polybutyleneterephthalate, polyethylenes, polyamides, polyimides, epoxides, or mixtures thereof. 
     
     
       8. The apparatus of claim 1 wherein the septal defect closure device is made of a polymeric material selected from the group consisting of collagen I, collagen III, collagen IV, glycosaminoglycans, chondroitin sulfate or composites thereof. 
     
     
       9. The apparatus of claim 4 wherein the septal defect closure device is made of a carbon fiber composite coated with a material selected from the group consisting of polycarbonate urethanes, polyether urethanes, polyethyleneterephthalate, polybutyleneterephthalate, polyethylenes, polyimides, polyamides, epoxides, or mixtures thereof. 
     
     
       10. The apparatus of claim 1 wherein the septal defect closure device is made a biocompatible inert metallic material. 
     
     
       11. The apparatus of claim 10 wherein the metallic material is solid. 
     
     
       12. The apparatus of claim 10 wherein the metallic material is woven. 
     
     
       13. The apparatus of claim 10 wherein the metallic material is braided. 
     
     
       14. The apparatus of claim 10 wherein the metallic material is selected from the group consisting of stainless steel, spring steel, memory shape metals, and metal alloys. 
     
     
       15. The apparatus of claim 14 wherein the metallic material is nitinol. 
     
     
       16. The apparatus of claim 10 wherein the septal defect closure device is made of a metal fiber coated with a polymeric material. 
     
     
       17. The apparatus of claim 1 further comprising a covering material partially or completely covering the septal defect closure device. 
     
     
       18. The apparatus of claim 17 wherein the covering material is fabric. 
     
     
       19. The apparatus of claim 17 wherein the covering material is an elastic material. 
     
     
       20. The apparatus of claim 17 wherein the covering material is selected from the group consisting of polyamides, nylon 6, nylon 6,6, polyesters, PET, polyethers, fluorinated polymers, polytetrafluoroethylene, biodegradable or nonbiodegradable fibers derived from natural sources such as carbohydrates, collagens, and proteins, and mixtures thereof. 
     
     
       21. The apparatus of claim 17 wherein the covering material is biodegradable. 
     
     
       22. The apparatus of claim 17 wherein the covering material is a polymeric material. 
     
     
       23. The apparatus of claim 22 wherein the polymeric material is further coated with a natural material. 
     
     
       24. The apparatus of claim 23 wherein the natural material is selected from the group consisting of collagen I, collagen III, collagen IV, glycosaminoglycans, chondroitin sulfate or composites thereof. 
     
     
       25. The apparatus of claim 1 further comprising locking means whereby the device may lock into the second configuration thereof, said locking means being constructed and arranged to prevent the device from resuming its cylindrical configuration. 
     
     
       26. The apparatus of claim 25 wherein the locking means comprises a first locking location positioned at a proximal end of the device, a second locking location positioned at the central portion of the device and a third locking location position at a distal end of the device. 
     
     
       27. The apparatus of claim 1 wherein the struts are made of metal and are coated with a polymeric material. 
     
     
       28. The septal defect closure device of claim 1 constructed and arranged in a reversible plug-like conformation including oppositely disposed sealing surfaces which fit securely around opposite sides of the defect after being positioned therein. 
     
     
       29. The apparatus of claim 25 wherein the locking means comprises at least one locking location positioned on one of the at least two struts. 
     
     
       30. A method of reversibly closing a septal defect comprising the steps of: a) providing an apparatus for reversibly closing a septal defect, the apparatus comprising: i) a septal defect closure device that is unitary in construction and comprises a first end, a second end, a center portion and having a first configuration comprising a cylindrical shaft having an axis therethrough and a plurality of concentric parallel cuts therethrough,   ii) a catheter delivery means; and   iii) an intralumen mechanical mechanism located in the catheter delivery means;     b) delivering the apparatus to an area having a septal defect;   c) positioning the center portion of the shaft of the device in the septal defect;   d) pulling the first and second ends of the shaft toward the center portion thereof, by means of the intralumen mechanical mechanism, thereby creating at least two flattened support struts which move radially away from the axis in a hinge like fashion;   e) moving the struts radially away from the axis in a hinge like fashion, by means of the intralumen mechanical mechanism, thereby causing the septal defect closure device to assume a specific second configuration which fits securely into the septal defect, spanning both sides thereof and is anchored thereto by pressure, causing the defect to be reversibly closed.